December 4, 2024

Archives for January 26, 2024

NGC 2261 – Hubble’s Variable Nebula in Monoceros

Telescope: Astro-Tech 8” f/8 Ritchey-Chretien, Orion Atlas EQ-G

Camera: Canon EOS Ra, Baader Mk III MPCC, GSO IR Blocking Filter

Guide scope: Astro-Tech 60mm, ZWO ASI120MM mini, PHD2

Exposure: 56x60sec, gain ISO 1600 saved as RAW, dithered every 2 images

Darks: Internal

Flats: 64×1/250sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency

Lensed Sky Quality Meter: 18.3

Stacking: Average, 1 sigma clip

White Balance: Nebulosity Automatic

Software: Backyard EOS, Deep Sky Stacker, Nebulosity, Photoshop

Hubble’s Variable nebula is a small, bright, fan-shaped reflection nebula in Monoceros (the Unicorn). The bright tip of the nebula is not just a star, but a dense nebula hiding a binary system at its core (R Mon). Clouds of dust are believed to orbit this system, casting shadows up onto the veil causing the overall brightness of the nebula to vary. Time lapse sequences spanning weeks of time show the shadows sweeping across the nebula. Visually, NGC 2261 appears very much like a beautiful fan-shaped comet. In fact, it appears more like a comet than some comets!

NGC 2261 is presently rising in the east as the sky darkens.